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 Add this item to the list  810153 Original description
Description type:Original description 
Description:Perithecia formed heterothallically in vitro, disposed solitarily or in groups, developing directly on the agar surface or on sterile pieces of birch wood, ovoid to obpyriform, darkred, becoming purple-red in 3 % KOH (positive colour reaction), smooth to finely warted, 210e270 260e320 mm high when rehydrated; without recognisable stroma; perithecial wall consisting of two poorly distinguishable regions; outer region 17e30 mm thick, composed of 1e3 layers of angular to subglobose cells, 13e22 7e13 mm; cell walls up to 2 mmthick; inner up to 10 mm thick, composed of cells that are flat in transverse optical section and angular to oval in subsurface optical face view; walls in the outer and inner regionsometimes locally thinning to form pseudopores in conjunction with matching structures in adjacent cells. Asci clavate to narrowly clavate, ca. 55e65 8e10 mm, eight-spored; apex rounded, with a minutely visible ring. Ascospores divided into two cells of equal size, ellipsoid to oblong-ellipsoid, somewhat tapering towards the ends, smooth to finely warted, (10.1e)13.9(e15.8) (4.1e)5.3(e6.4) mm. Conidiophores simple or complex, sporodochial. Simple conidiophores arising laterally or terminally fromaerialmycelium, solitary to loosely aggregated, unbranched or sparsely branched, bearing up to three phialides, 1e6-septate, 28e180 mm long; phialidesmonophialidic,more or less cylindrical,with slight taper towards the apex, 18e40 mm long, 2.0e3.5 mm wide at the base, 2.5e3.5 mm at the widest point, and 1.5e2.5 mm wide at the apex. Complex conidiophores aggregated in small sporodochia, repeatedly and irregularly branched; phialides more or less cylindrical, but tapering slightly in the upper part towards the apex, or narrowly flask-shaped, mostly with widest pointnear the middle, 17e22 mm long, 2.5e3.0 mm wide at the base, 3.5e4.0 mm at the widest point, and 1.5e2.0 mm wide near the apex. Macroconidia predominating, formed on both types of conidiophores; on SNA formed in flat domes of slimy masses, (1e)3(e4)-septate, straight or minutely curved, cylindrical, or with minute widening towards the tip, appearing somewhat clavate, particularly when still attached to the phialide, with apex or apical cell typically slightly bent to one side and minutely beaked; base mostly with a visible, centrally located or laterally displaced hilum; one-septate conidia (20.0e) 26.5e27.7e28.9(e43.0) (4.5e)5.5e5.6e5.8(e7.0) mm, with a length:width ratio of (3.3e)4.7e4.9e5.1(e7.2) mm, twoseptate conidia (24.0e)31.4e32.5e33.6(e44.0) (5.0e)6.0e6.2e 6.4(e8.0) mm, with a length:width ratio of (3.7e)5.1e5.2e5.4 (e6.7) mm, and three-septate conidia (30.0e)38.3e39.4e 40.6(e56.0) (5.0e)6.7e6.8e7.0(e9.0) mm, with a length:width ratio of (4.3e)5.7e5.8e6.0(e7.9) mm.Microconidia 0e1-septate, ellipsoidal to ovoid, more or less straight, with a minutely or clearly laterally displaced hilum,with a constriction on the septum; zero-septate microconidia (9.0e)11.8e12.3e12.7(e16.0) (3.5e)4.2e4.3e4.4(e5) mm with a length:width ratio of (2.0e) 2.8e2.9e3(e4.0) mm, one-septate conidia (11.0e)15.0e15.5e 16.0(e20.0) (3.5e) 4.3e4.4e4.5(e5.5) mm with a length:width ratio of (2.4e)3.4e3.6e3.7(e4.8) mm. Conidia formed in heads on simple conidiophores or as white (OA) or unpigmented (SNA) masses, as well as on complex conidiophores. Chlamydospores rarely occur, globose to subglobose, 6e15 5e13 mm, smooth but often appearing rough due to deposits, thick-walled, mostly occurring in chains. 
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